of canton



Feb. 7, 1928. 1,658,377

H. c. HAIGHT METHOD OF FORGING INSULATOR CAPS Filed y 7. 1925 2 Sheets-Sheet l Haffag'yfii Q W%W Feb. 7, 1928.

H. C. HAIGHT METHOD OF FORGING INSULATOR CAPS F'iled y 7. 1923 2 Sheets-Sheet 2 Patented Feb. 7, 1928.

UNITED STATES PATENT OFFICE.

IH ZABRY G. HAIGHT, OF CANTON, OHIO, ASSIGNOR TO THE AMERICAN FORGE AND MACHINE COMPANY, OF CANTON, OHIO, A CORPORATION OF OHIO.

METHOD OF FORGING INSULATOR CAPS.

Application filed May 7,

The invention relates to metal insulator caps used for supporting high tenslon con: ductors, and to the particular cup shaped type in which a slotted dome and a transb verse partition forms a recess for receiving and engaging the head of a supporting bolt.

The object of the improvement 1s to make the cap by a forging process, as dlstmguished from a casting process, and the new method of making such a cap involves the forging of a cup shaped body, the separate forging of the dome shaped top, and then securing the dome to the cup by means of electric welding or the like.

The several steps of the process are lllustrated in the accompanylng drawings, forming part hereof, in which Figure 1 is a side elevation of an lnsulator, showing its head and cap 1n section;

Fig. 2, a perspective view of a cyllndrlc blank from which the cup may be made;

Fig. 3, a sectional View of a p unch and die by which the cup may be initlally forged; Fig. 4, a sectional view of a cup body as 25 the same is initially formed;

Fig. 5, a sectional view of a punch and die by which a rim groove maybe formed;

Fig. 6, a sectional view showing the cup body with a rim groove formed therein;

Fig. 7 a sectional view showlng a punch and die by which the dome body may be forged;

8, a sectional view of the dome body as forged with a slotted opemng, for re- 35 ceiving the head of a supporting bolt there- Fig. 9, a side elevation, one half in section, showing the dome body Welded to'the cup body;

Fig. 10, a top view of the completed cap; and

Fig. 11, a fragmentary sectional view showing the method of inserting a bolt through the slot into the dome recess.

Similar numerals of reference refer to similar parts throughout the drawings.

The cap 12 for the head 13 of an insulator 14: may be provided with a dome 15 on its closed end, having a slotted opening 16 in 50 its top and forming a recess 17 for receivin the head 18 of a supporting bolt 19; an may be provided with apertures 20 hits side to receive a cotter pin 21 for pressing 1923. Serial No. 637,173.

the head of the bolt upward against the rim of the opening, all as shown in Fig. 1.

Such a cap may be made by initially forgmg from a cylindric blank 22 an inverted cup-shaped body 12, and at the same time forming an off-set 23 at the rim of the cup; which forging may be done by a punch 24 and a die 25, as shown in Fig. 3, and the ofi-set rim may be bent inward to form an internal annular groove 26 in the rim of the cup by means of a punch 27 and a die 28, as shown in Fig. 5.

A dome body 15 may be forged by a punch 29 and a die 30, as shown in Fig. 7, and the same may be formed with a slotted openlng 16 as shown in Fig. 8. The rim of the dome may then be secured to the inverted bottom of the cup by electric welding or the llke, to complete the cap as shown in Fig. 9.

When the dome is secured to the cup by electric welding, a rib 31 or 31 is preferably forged on each member to furnish 7 stock for the welding process.

The slotted opening 16 in the top of the dome 15 is formed with an elliptical openmg centrally located in the top of the dome having a notch extending from one side thereof, thus forming what may be termed a key-hole slot; the major axis of the elliptical opening being long enough to receive the head of the bolt by inclining the shank thereof to enter the notch, as shown in Fig. 11.

After the head of the bolt has been entered into the recess 17 in the manner shown in Fig. 11, the shank is rotated so as to align the axis of the bolt with the axis of the cap, as shown in Fig. 1, whereupon the cotter pin 21 may be entered through apertures 20 rovided for that purpose for holding the olt in the position shown in Fig. 1.

This formation of a key-hole slot in the top of the dome, permits the dome body 15 to be made without any breaks in its peripheral portion, so that the entire circumference or rim of the same may be joined to the closed end of the cup, thus giving the maximum strength to the insulator and especially to the walls of the recess socket in which the bolt head is received and secured.

I claim:

1. The method of making an insulator cap or the like, which includes forging an in- Q esser? verted on body and forginga se arate dome cup, there being an annular rib forged on body wit a continuous rim an a key-hole each member to furnish stock for welding slot in its top, and then welding the rim of them together. the dome to the inverted bottom of the cup. I 3. The method of making an insulator 5 2. The method of making an insulator c'ap cap or the like, which includes forging an 15 or the like which includes forging an ininverted cup body and forging a separate verted cuE body and forging a separate dome dome body with a rim thereon and slot there body wit a continuous rim and a key-hole in, and then welding the rim of the dome to slot in its top, and then welding the rim the inverted bottom of the on 10 of the dome to the inverted bottom of the HARRY C. J I 

